A blood clot that forms in a blood vessel or in the heart and does not move to another area of the body is called a thrombus, according to the U.S. National Library of Medicine. If the clot forms in a vessel or the heart but moves to another part of the body, it is called an embolus.
Blood clots can cause complications by attaching to the wall
of a blood vessel and blocking the flow of blood to or from that
vessel. Such a blockage prevents surrounding tissues from receiving
necessary blood and oxygen, which can permanently damage or even
kill those tissues.
New Drug For Deep Vein Thrombosis Eases Treatment Regimen
Main Category: Cardiovascular / Cardiology News
Article Date: 11 Dec 2006 - 0:00 PST
Deep vein thrombosis (DVT) occurs when a clot forms in one of
the inner veins of the leg and can worsen into pulmonary embolism
if the clot breaks away and travels to the lungs. Nearly 300,000
people in the United States die each year from these blood clots,
greater than the number of people who die from AIDS, breast cancer,
and automobile accidents combined. A study on a new drug for these
conditions, which can be taken less often than the current treatment
and therefore ease the burden faced by some patients, is being
presented today during the 48th Annual Meeting of the American
Society of Hematology (ASH(TM)).
"In the past decade, the introduction of low-molecular-weight
heparin was a major breakthrough in the treatment of venous blood
clots, paving the way for outpatient treatment. Now, idraparinux
has the potential to further advance the treatment of this common
-- and potentially deadly -- condition," said ASH President
Kanti R. Rai, MD, of Long Island Jewish Medical Center and the
Albert Einstein College of Medicine.
The limitations of current treatments include the need for daily
injections, adverse interactions with food and many types of drugs,
and a wide variation in treatment results requiring intensive
monitoring of patients. More than 5,000 patients (2,904 with deep
vein thrombosis and 2,215 with pulmonary embolism) participated
in this comparative study looking at standard treatment versus
idraparinux.
Patients were randomized to either receive idraparinux (by subcutaneous
injection once a week) or the standard daily treatment regimen
of low- molecular-weight heparin followed by a vitamin K inhibitor
for three to six months. The researchers' primary measure of success
was whether a symptomatic venous clot would reoccur three months
after treatment.
In the DVT group, idraparinux was found to be just as effective
as the low-molecular-weight heparin regimen, with a nearly identical
incidence of reoccurrence: 2.9 percent in the patients taking
idraparinux and 3 percent in the control group. Severe bleeding
-- a common side effect of anticoagulants - - occurred in 4.5
percent of the DVT patients taking idraparinux and in 7 percent
of those receiving traditional treatment. By six months, the bleeding
rates became similar.
In the pulmonary embolism group, the incidence of blood clot
reoccurrence after three months was 1.6 percent in the control
group and higher -- 3.4 percent -- in those taking idraparinux,
showing that the new drug was not as effective as the standard
treatment in these patients.
"Although the results for idraparinux in the pulmonary embolism
group were surprising and disappointing, for patients with deep
vein thrombosis our findings should have a remarkable impact,"
said Harry Buller, MD, Chairman of the Department of Vascular
Medicine at the Academic Medical Center in Amsterdam and lead
study author. "The fact that once-a-week injections of idraparinux
are just as effective and safe as traditional treatment frees
patients with DVT from the daily injections and continuous monitoring
that would otherwise be required."
The American Society of Hematology (http://www.hematology.org)
is the world's largest professional society concerned with the
causes and treatment of blood disorders. Its mission is to further
the understanding, diagnosis, treatment, and prevention of disorders
affecting blood, bone marrow, and the immunologic, hemostatic,
and vascular systems, by promoting research, clinical care, education,
training, and advocacy in hematology.
American Society of Hematology
http://www.hematology.org
Clexane (REG) / Lovenox (REG) More Effective For Preventing
Venous Thromboembolism In Patients With Acute Ischemic Stroke
Main Category: Stroke / Neuroprotection News
Article Date: 16 Dec 2006 - 7:00 PST
Sanofi-aventis has announced that the results of the PREVAIL (Prevention
of VTE after Acute Ischemic Stroke with LMWH Enoxaparin) study
presented at the 48th American Society of Hematology (ASH) annual
meeting in Orlando demonstrated a significant 43% reduction in
venous thromboembolism (VTE) events with enoxaparin vs. unfractionated
heparin (UFH) in medically ill patients who suffered an acute
ischemic stroke.
Among medically-ill patients, stroke patients are at an increased
risk for developing VTE. Without VTE prophylaxis, up to 75% of
patients with hemiplegia following stroke develop deep-vein thrombosis
(DVT) and 20% develop pulmonary embolism (PE) (1, 2).
The primary efficacy endpoint of the study was the composite
of symptomatic or asymptomatic DVT, symptomatic and / or fatal
PE during the treatment period.
The significant 43% relative risk reduction in VTE events observed
with enoxaparin vs. UFH for the primary efficacy endpoint (10.2
% vs. 18.1%; p= 0.0001) was associated with a consistent reduction
in proximal DVT by 53% (4.5% vs. 9.6%; p=0.0003).
There was no significant difference in clinically important bleedings
(1.3% vs. 0.7%, p = 0.20), corresponding to the combination of
both symptomatic intracranial bleeding, the most serious complication,
and major extracranial bleeding.
The reduction in VTE risk was also observed in patients presenting
with different levels of stroke severity, with no significant
difference in clinically important bleeding.
"Balancing the benefits of lowering the risk of VTE while
minimizing the risk of bleeding is a very important element in
choosing prophylactic regimens for this particularly fragile patient
population, as it combines the usual factors of VTE in addition
to the stroke context," said Dr. David Sherman, Professor
in the Division of Neurology in the Department of Medicine at
the University of Texas Health Science Center (UTHSC) in San Antonio,
and principal investigator of the study. "PREVAIL showed
that enoxaparin, when compared to UFH, had a superior efficacy
with no significant increase in clinically important bleedings.
These data provide new evidence that suggests enoxaparin can be
used as VTE prophylaxis in this high risk population".
###
About Venous Thromboembolism (VTE)
Venous thromboembolism is a general term used to describe the
formation of a blood clot (thrombus) that blocks a vessel. This
may occur in any part of the venous system, but the most common
manifestations are deep-vein thrombosis (DVT), usually in the
leg, and pulmonary embolism (PE).
VTE is also a common complication among individuals who have
experienced an acute ischemic stroke (AIS).
About PREVAIL
PREVAIL trial is the first large-scale, multinational, prospective,
randomized study which enrolled 1,762 ischemic stroke patients
(stratified by NIH Stroke Scale Score) in over 15 countries.
Patients confirmed with an acute ischemic stroke, were randomized
within 48 hours of stroke symptoms to receive enoxaparin daily
40 mg SC or UFH 5000 IU SC Q 12 treatment for 10 days +/- 4 days
with a follow up period of 90 days and stratified by NIH Stroke
Scale Score (severe greater than or equal to 14 and less severe
<14).
The primary efficacy endpoint was the composite of symptomatic
or asymptomatic DVT, symptomatic ad / or fatal PE during the treatment
period. The primary safety endpoints included symptomatic intracranial
bleeding, major extracranial bleeding and all-cause mortality.
About Enoxaparin
Enoxaparin is an anticoagulant of the low molecular weight heparin
(LMWH) class. Its clinical applications are linked to its antithrombotic
properties. It is used to inhibit clot formation in venous or
arterial vessels to avoid potential acute or chronic complications
of venous or arterial thrombosis such as pulmonary embolism, myocardial
infarction or death of cardiovascular origin. As with all anticoagulants,
the most frequently reported side effect for enoxaparin is bleeding.
Clinical indications for enoxaparin may vary from one country
to another.
About sanofi-aventis
Sanofi-aventis is the world's third largest pharmaceutical company,
ranking number one in Europe. Backed by a world-class R&D
organization, sanofi-aventis is developing leading positions in
seven major therapeutic areas: cardiovascular, thrombosis, oncology,
metabolic diseases, central nervous system, internal medicine,
and vaccines. Sanofi-aventis is listed in Paris (EURONEXT: SAN)
and in New York (NYSE: SNY).
Contact: Salah Mahyaoui
References:
1. McCarthy ST, Turner J. Low-dose subcutaneous heparin in the
prevention of deep-vein thrombosis and pulmonary emboli following
acute stroke. Age Ageing 1986; 15: 84-8
2. McCarthy ST, Turner JJ, Robertson D, Hawkey CJ, Macey DJ.
Low-dose heparin as a prophylaxis against deep-vein thrombosis
after acute stroke. Lancet 1977: 2: 800-1.
Source: Sanofi-Aventis Press Release
For further information please go to:
Sanofi-Aventis, U.K.
Sanofi-Aventis, U.S.
Sanofi-Aventis, France
